The present invention relates to a process for manufacturing fiberboard and particularly hardboard and medium density fiberboard having improved dimensional stability properties.
It is known to manufacture board products by consolidating of joining refined lignocellulosic fibers using a chemical binder, pressure and heat. Typical binders are thermosetting resins such as urea-formaldehyde, phenol-formaldehyde, resorcinol-formaldehyde, condensed furfuryl alcohol resins or organic polyioscyanates. The binder is added to the lignocellulosic raw materials or fibers, and the mixture or "furnish" is compressed under heat to bond the material together in a densified form.
Problems encountered in known fiberboards include formaldehyde emissions from the boards, poor water adsorption properties, and the fact that the boards are non-durable under exterior and/or moist service conditions.
Accordingly, the present inventor recognized the need for an economical process for manufacturing fiberboard having improved physical characteristics.